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Air-water tests in support of LLTR series II Test A-4. [Large Leak Test Rig]

Description: A series of tests injecting air into a tank of stagnant water was conducted in June 1980 utilizing the GE Plenum Mixing Test Facility in San Jose, California. The test was concerned with investigating the behavior of air jets at a submerged orifice in water over a wide range of flow rates. The main objective was to improve the basic understanding of gas-liquid phenomena (e.g., leak dynamics, gas bubble agglomeration, etc.) in a simulated tube bundle through visualization. The experimental results from these air-water tests will be used as a guide to help select the leak size for LLTR Series II Test A-4 because air-water system is a good simulation of water-sodium mixture.
Date: July 1, 1980
Creator: Chen, K.
Partner: UNT Libraries Government Documents Department

REVISED STREAM CODE AND WASP5 BENCHMARK

Description: STREAM is an emergency response code that predicts downstream pollutant concentrations for releases from the SRS area to the Savannah River. The STREAM code uses an algebraic equation to approximate the solution of the one dimensional advective transport differential equation. This approach generates spurious oscillations in the concentration profile when modeling long duration releases. To improve the capability of the STREAM code to model long-term releases, its calculation module was replaced by the WASP5 code. WASP5 is a US EPA water quality analysis program that simulates one-dimensional pollutant transport through surface water. Test cases were performed to compare the revised version of STREAM with the existing version. For continuous releases, results predicted by the revised STREAM code agree with physical expectations. The WASP5 code was benchmarked with the US EPA 1990 and 1991 dye tracer studies, in which the transport of the dye was measured from its release at the New Savannah Bluff Lock and Dam downstream to Savannah. The peak concentrations predicted by the WASP5 agreed with the measurements within {+-}20.0%. The transport times of the dye concentration peak predicted by the WASP5 agreed with the measurements within {+-}3.6%. These benchmarking results demonstrate that STREAM should be capable of accurately modeling releases from SRS outfalls.
Date: May 1, 2005
Creator: Chen, K
Partner: UNT Libraries Government Documents Department

COMPARISONS FOR RAMS MODELS (V3A, V4.3 AND V6.0)

Description: The Regional Atmospheric Modeling System (RAMS) is an atmospheric numerical model developed by scientists at Colorado State University and the ASTER Division of Mission Research Corporation for simulating and forecasting meteorological phenomena. RAMS v3a and v4.3 are being used by the Savannah River National Laboratory (SRNL) as an operational tool for weather forecast and emergency response for the Savannah River Site (SRS). ATmospheric, Meteorological, and Environmental Technologies (ATMET) is now the proprietor of RAMS. The latest upgrade (v6.0) was officially released on January 11, 2006. ATG plans to eventually replace the RAMS v3a and v4.3 with the RAMS v6.0 for operational site forecasting if the newest version provides a significant improvement in the numerical forecast. A study to compare the three model (v3a, v4.3 and v6.0) results with respect to surface stations observations was conducted and is the subject of this report. Two cases were selected for simulation by these three RAMS models. One simulation started at 0 Z on April 3, 2007 and represents a warm weather case (high temperature of 26 C and low temperature of 16 C) at SRS, while the other simulation started at 0 Z on April 7, 2007 and represents a cold weather case (high temperature of 9 C and low temperature of -1 C) at SRS. The wind speeds, wind directions, temperatures and the dew point temperatures predicted by the three RAMS models were interpolated to 46 surface observation locations. The interpolated results were compared with the observation data. Statistically, the differences between the three model results were very small. For the present configurations, the predictions from RAMS v6.0 are no better than the older models with the exception of wind direction. The proposed path forward would be to fine tune the RAMS v6.0 model input parameters to improve the predictions. This should ...
Date: August 30, 2007
Creator: Chen, K
Partner: UNT Libraries Government Documents Department

LAGRANGIAN PARTICLE DISPERSION MODEL (LPDM) TECHNICAL DESCRIPTION (U)

Description: The Savannah River National Laboratory (SRNL) uses the Lagrangian Particle Dispersion Model (LPDM) in conjunction with the Regional Atmospheric Modeling System as an operational tool for emergency response consequence assessments for the Savannah River Site (SRS). The LPDM is an advanced stochastic atmospheric transport model used to transport and disperse passive tracers subject to the meteorological field generated by RAMS from sources of varying number and shape. The Atmospheric Technologies Group (ATG) of the SRNL is undertaking the task of reviewing documentation and code for LPDM Quality Assurance (QA). The LPDM QA task will include a model technical description, computer coding descriptions, model applications, and configuration control. This report provides a comprehensive technical description of the LPDM model.
Date: July 20, 2006
Creator: Chen, K
Partner: UNT Libraries Government Documents Department

EFFECT OF CLIMATE CHANGE ON WATERSHED RUNOFF FLOW - UPPER COOSA RIVER BASIN UPSTREAM FROM PLANT HAMMOND

Description: The ability of water managers to maintain adequate supplies in the coming decades depends on future weather conditions, as climate change has the potential to reduce stream flows from their current values due to potentially less precipitation and higher temperatures, and possibly rendering them unable to meet demand. The upper Coosa River basin, located in northwest Georgia, plays an important role in supplying water for industry and domestic use in northern Georgia, and has been involved in water disputes in recent times. The seven-day ten-year low flow (7Q10 flow) is the lowest average flow for seven consecutive days that has an average recurrence interval of 10 years. The 7Q10 flow is statistically derived from the observed historical flow data, and represents the low flow (drought) condition for a basin. The upper Coosa River basin also supplies cooling water for the 935MW coal-fired Hammond plant, which draws about 65% of the 7Q10 flow of the upper Coosa River to dissipate waste heat. The water is drawn through once and returned to the river directly from the generator (i.e., no cooling tower is used). Record low flows in 2007 led to use of portable cooling towers to meet temperature limits. Disruption of the Plant Hammond operation may trigger closure of area industrial facilities (e.g. paper mill). The population in Georgia is expected to double from 9 million to 18 million residents in the next 25 years, mostly in the metropolitan Atlanta area. Therefore, there will be an even greater demand for potable water and for waste assimilation. Climate change in the form of persistent droughts (causing low flows) and high ambient temperatures create regulatory compliance challenges for Plant Hammond operating with a once-through cooling system. Therefore, the Upper Coosa River basin was selected to study the effect of potential future weather change ...
Date: October 24, 2011
Creator: Chen, K.
Partner: UNT Libraries Government Documents Department

STREAM II-V5: REVISION OF STREAM II-V4 AQUEOUS TRANSPORT CODE TO ACCOUNT FOR THE EFFECTS OF RAINFALL EVENTS

Description: STREAM II is an aqueous transport model developed by the Savannah River National Laboratory (SRNL) for use in the Savannah River Site (SRS) emergency response program. The transport model of the Water Quality Analysis Simulation Program (WASP) is used by STREAM II to perform contaminant transport calculations. WASP5 is a US Environmental Protection Agency (EPA) water quality analysis program that simulates contaminant transport and fate through surface water. A recent version of the code (STREAM II-V4) predicts peak concentration and peak concentration arrival time at downstream locations for releases from the SRS facilities to the Savannah River. The input flows for STREAM II-V4 are derived from the historical flow records measured by the United States Geological Survey (USGS). The stream flow for STREAM II-V4 is fixed and the flow only varies with the month in which the releases are taking place. Therefore, the effects of flow surge due to a severe storm are not accounted for by STREAM IIV4. STREAM II-V5 is an upgraded version which accounts for the effects of a storm event. The revised model finds the proper stream inlet flow based on the total rainfall and rainfall duration as input by the user. STREAM II-V5 then adjusts the stream segment volumes (cross sections) based on the stream inlet flow. The rainfall based stream flow and the adjusted stream segment volumes are then used for contaminant transport calculations. This paper will discuss the required modifications to STREAM II and a comparison of results between the older and newer versions for an example involving a rainfall event.
Date: May 18, 2011
Creator: Chen, K.
Partner: UNT Libraries Government Documents Department

STREAM II-V5: REVISION OF STREAM II-V4 TO ACCOUNT FOR THE EFFECTS OF RAINFALL EVENTS

Description: STREAM II-V4 is the aqueous transport module currently used by the Savannah River Site emergency response Weather Information Display (WIND) system. The transport model of the Water Quality Analysis Simulation Program (WASP) was used by STREAM II to perform contaminant transport calculations. WASP5 is a US Environmental Protection Agency (EPA) water quality analysis program that simulates contaminant transport and fate through surface water. STREAM II-V4 predicts peak concentration and peak concentration arrival time at downstream locations for releases from the SRS facilities to the Savannah River. The input flows for STREAM II-V4 are derived from the historical flow records measured by the United States Geological Survey (USGS). The stream flow for STREAM II-V4 is fixed and the flow only varies with the month in which the releases are taking place. Therefore, the effects of flow surge due to a severe storm are not accounted for by STREAM II-V4. STREAM II-V4 has been revised to account for the effects of a storm event. The steps used in this method are: (1) generate rainfall hyetographs as a function of total rainfall in inches (or millimeters) and rainfall duration in hours; (2) generate watershed runoff flow based on the rainfall hyetographs from step 1; (3) calculate the variation of stream segment volume (cross section) as a function of flow from step 2; (4) implement the results from steps 2 and 3 into the STREAM II model. The revised model (STREAM II-V5) will find the proper stream inlet flow based on the total rainfall and rainfall duration as input by the user. STREAM II-V5 adjusts the stream segment volumes (cross sections) based on the stream inlet flow. The rainfall based stream flow and the adjusted stream segment volumes are then used for contaminant transport calculations.
Date: February 1, 2010
Creator: Chen, K.
Partner: UNT Libraries Government Documents Department

Compatibility of aluminide-coated Hastelloy x and Inconel 617 in a simulated gas-cooled reactor environment

Description: Commercially prepared aluminide coatings on Hastelloy X and Inconel 617 substrates were exposed to controlled-impurity helium at 850/sup 0/ and 950/sup 0/C for 3000 h. Optical and scanning electron (SEM) microscopy, electron microprobe profiles, and SEM X-ray mapping were used to evaluate and compare exposed and unexposed control samples. Four coatings were evaluated: aluminide, aluminide with platinum, aluminide with chromium, and aluminide with rhodium. With extended time at elevated temperature, nickel diffused into the aluminide coatings to form epsilon-phase (Ni/sub 3/Al). This diffusion was the primary cause of porosity formation at the aluminide/alloy interface.
Date: March 1, 1982
Creator: Chin, J.; Johnson, W. R. & Chen, K.
Partner: UNT Libraries Government Documents Department

STREAM II-V4: Revision for STREAM II-V3 to Allow Mouse-Driven Selection of Release Location from a Graphical User Interface

Description: STREAM II-V3 is an aqueous transport module of the Savannah River Site emergency response Weather INformation Display (WIND) system. Stream II-V3 predicts peak concentration and peak concentration arrival time at downstream locations for releases from the SRS facilities to the Savannah River. Fifteen pre-determined potential release locations from SRS facilities were built into the current STREAM II-V3 model. Therefore, STREAM II-V3 can not be used for situations in which release locations differ from the fifteen pre-determined locations. To eliminate this limitation, STREAM II-V3 was upgraded. The revised STREAM II-V4 allows users to select the release location anywhere along the specified SRS main streams or the Savannah River by mouse clicking on a map displayed on the computer monitor.
Date: December 18, 2002
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Revised STREAM code benchmarking with 1991 K-reactor tritiated aqueous release incident

Description: The transport and diffusion module of the WIND System aqueous emergency response program (STREAM code) was replaced with the EPA WASP5 code. A set of input data was developed to model the transport of pollutants from a release point in K-Area to Savannah, Georgia through Indian Grave Branch, Pen Branch, the SRS swamp, Steel Creek, and the Savannah River. To evaluate the modifications to the STREAM code, data from an accidental release of tritiated water from K-Reactor in 1991 were used for benchmarking. A leak in a heat exchanger allowed a small amount of reactor coolant water to be released to cooling streams onsite, eventually reaching the Savannah River. Measurements of tritium concentration were taken at several downstream locations during the release. The results show that the revised STREAM code overpredicts the peak concentrations by 3 to 15%, which is comparable to the measurement uncertainty (one standard deviation). The revised STREAM code underpredicts the transport times of the concentration peak by 18 to 37%. The discrepancies in the travel time could result from uncertainties in the start of the release. The revised STREAM code performed well in simulating both the timing and the magnitude of the maximum observed tritium concentration. This gives confidence that the code can perform well both for emergency response and other engineering or safety analyses
Date: April 25, 1996
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Surface Water Modeling Using an EPA Computer Code for Tritiated Waste Water Discharge from the heavy Water Facility

Description: Tritium releases from the D-Area Heavy Water Facilities to the Savannah River have been analyzed. The U.S. EPA WASP5 computer code was used to simulate surface water transport for tritium releases from the D-Area Drum Wash, Rework, and DW facilities. The WASP5 model was qualified with the 1993 tritium measurements at U.S. Highway 301. At the maximum tritiated waste water concentrations, the calculated tritium concentration in the Savannah River at U.S. Highway 301 due to concurrent releases from D-Area Heavy Water Facilities varies from 5.9 to 18.0 pCi/ml as a function of the operation conditions of these facilities. The calculated concentration becomes the lowest when the batch releases method for the Drum Wash Waste Tanks is adopted.
Date: June 1, 1998
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

7Q10 flows for SRS streams

Description: The Environmental Transport Group of the Environmental Technology Section was requested to predict the seven-day ten-year low flow (7Q10 flow) for the SRS streams based on historical stream flow records. Most of the historical flow records for the SRS streams include reactor coolant water discharged from the reactors and process water released from the process facilities. The most straight forward way to estimate the stream daily natural flow is to subtract the measured upstream reactor and/or facility daily effluents from the measured downstream daily flow. Unfortunately, this method does not always work, as indicated by the fact that sometimes the measured downstream volumetric flow rates are lower than the reactor effluent volumetric flow rates. For those cases that cannot be analyzed with the simple subtracting method, an alternative method was used to estimate the stream natural flows by statistically separating reactor coolant and process water flow data. The correlation between the calculated 7Q10 flows and the watershed areas for Four Mile Branch and Pen Branch agrees with that calculated by the USGS for Upper Three Runs and Lower Three Runs Creeks. The agreement between these two independent calculations lends confidence to the 7Q10 flow calculations presented in this report.
Date: October 1, 1996
Creator: Chen, K. F.
Partner: UNT Libraries Government Documents Department

STREAM2 for Aqueous Release Emergency Response

Description: This report documents the STREAM2 code and its input models developed for the WIND System. STREAM2 is a modification of the STREAM code, which is the transport and diffusion module of the WIND System aqueous emergency response program. STREAM predicts downstream pollutant concentrations for releases from the Savannah River Site to the Savannah River. The STREAM calculation module uses an algebraic equation to approximate the solution of the differential one-dimensional advective transport equation. The advantage of this simplified approach is that the time required to obtain a solution is shortened to a matter of minutes. However, this approach generates spurious oscillations in the concentration profile when modeling long duration releases. To improve the capability of the STREAM code to model long-term releases, its calculation module was replaced by the transport module of the WASP5 code. WASP5 is a US EPA water quality analysis program that simulates pollutant transport and fate through surface water. The revised STREAM code is named STREAM2.
Date: September 23, 1998
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Benchmarking WASP5 with data from the 1991 K-Reactor tritiated aqueous release incident

Description: The Savannah River Site (SRS) has upgraded its aqueous emergency response capability to model the transport of pollutants released from SRS facilities during normal operation or accidents through onsite streams to the Savannah River. The transport and dispersion modules from the US Environmental Protection Agency (EPA) WASP5 model were incorporated into the SRS emergency response system, called the Weather Information and Display (WIND) System. WASP5 is a water quality analysis program that simulates surface water pollutant transport, using a finite difference method to solve the advective transport equation. Observed tritium concentrations in the SRS streams and the Savannah River from an accidental release from K-Reactor, one of the SRS nuclear material production reactors, were used to benchmark the new model. Although all SRS reactors have since been deactivated, this release of tritiated water occurred between December 22 and 25, 1991, through the K-Reactor secondary cooling water discharge. Analyses of reactor discharge water suggested the leak began sometime during December 22. The leak was positively identified and isolated on December 25. Following the release, tritium concentrations were tracked and measured as the tritiated water flowed from the K-Area outfall into Indian Grave Branch and pen Branch, through the Savannah River swamp, past the mouth of Steel Creek, and down the Savannah River. The measured tritium concentrations at Steel Creek, Highway 301, Becks Ferry and Abercorn Creek were used for benchmarking.
Date: November 7, 1996
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

STREAM2 Revision 1: An aqueous release emergency response model

Description: This report documents the revision for STREAM2 code and its input files. STREAM2 is an aqueous transport module of the WIND system. As requested by the Emergency Response Department, two surface aqueous release locations (McQueen Branch and Tims Branch) were added in the STREAM2 code. In addition, the revised STREAM2 has the capability to vary the channel-segment volume based on channel flow to better represent the open channel hydraulics. Thus, the updated version of STREAM2 improves the contaminant transport calculation
Date: April 14, 2000
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

1995 and 1996 Upper Three Runs Dye Study Data Analyses

Description: This report presents an analysis of dye tracer studies conducted on Upper Three Runs. The revised STREAM code was used to analyze these studies and derive a stream velocity and a dispersion coefficient for use in aqueous transport models. These models will be used to facilitate the establishment of aqueous effluent limits and provide contaminant transport information to emergency management in the event of a release.
Date: June 1998
Creator: Chen, K. F.
Partner: UNT Libraries Government Documents Department

Revised STREAM code and WASP5 benchmark

Description: STREAM is an emergency response code that predicts downstream pollutant concentrations for releases from the SRS area to the Savannah River. The STREAM code uses an algebraic equation to approximate the solution of the one dimensional advective transport differential equation. This approach generates spurious oscillations in the concentration profile when modeling long duration releases. To improve the capability of the STREAM code to model long-term releases, its calculation module was replaced by the WASP5 code. WASP5 is a US EPA water quality analysis program that simulates one-dimensional pollutant transport through surface water. Test cases were performed to compare the revised version of STREAM with the existing version. For continuous releases, results predicted by the revised STREAM code agree with physical expectations. The WASP5 code was benchmarked with the US EPA 1990 and 1991 dye tracer studies, in which the transport of the dye was measured from its release at the New Savannah Bluff Lock and Dam downstream to Savannah. The peak concentrations predicted by the WASP5 agreed with the measurements within {+-} 20.0%. The transport times of the dye concentration peak predicted by the WASP5 agreed with the measurements within {+-} 3.6%. These benchmarking results demonstrate that STREAM should be capable of accurately modeling releases from SRS outfalls.
Date: May 1, 1995
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Flood Hazard Recurrence Frequencies for C-, F-, E-, S-, H-, Y-, and Z-Areas

Description: A method was developed to determine the probabilistic flood elevation curves for Savannah River Site facilities. This report presents the method used to determine the probabilistic flood elevation curves for C-, F-, E-, H-, S-, Y-, and Z-Areas due to runoff from the Upper Three Runs and Fourmile Branch basins.
Date: November 18, 1999
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Pen Branch Delta and Savannah River Swamp Hydraulic Model

Description: The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions.
Date: May 13, 1999
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

The Effect of Sedimentation on Plutonium Transport in Fourmile Branch

Description: The major mechanisms of radioactive material transport and fate in surface water are sources, dilution, advection and dispersion of radionuclides by flow and surface waves, radionuclide decay, and interaction between sediment and radionuclides. STREAM II, an aqueous transport module of the Savannah River Site emergency response WIND system, accounts for the source term, and the effects of dilution, advection and dispersion. Although the model has the capability to account for nuclear decay, due to the short time interval of interest for emergency response, the effect of nuclear decay is very small and so it is not employed. The interactions between the sediment and radionuclides are controlled by the flow conditions and physical and chemical characteristics of the radionuclides and the sediment constituents. The STREAM II version used in emergency response must provide results relatively quickly; it therefore does not model the effects of sediment deposition/resuspension. This study estimates the effects of sediment deposition/resuspension on aqueous plutonium transport in Fourmile Branch. There are no measured data on plutonium transport through surface water available for direct model calibration. Therefore, a literature search was conducted to find the range of plutonium partition coefficients based on laboratory experiments and field measurements. A sensitivity study of the calculated plutonium peak concentrations as a function of the input parameter of partition coefficient was then performed. Finally, an estimation of the plutonium partition coefficient was made for the Fourmile Branch.
Date: February 21, 2002
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

STREAM II-V3: Revision for STREAM II-V2 to Include the Sedimentation Effects on a Release from H-Area

Description: STREAM II, an aqueous transport module of the Savannah River Site emergency response Weather INformation Display (WIND) system, accounts for the effects of dilution, advection and dispersion. Although the model has the capability to account for nuclear decay, due to the short time interval of interest for emergency response, the effect of nuclear decay is very small and so it is not employed. The interactions between the sediment and radionuclides are controlled by the flow conditions and physical and chemical characteristics of the radionuclides and the sediment constituents. The STREAM II-V2 used in emergency response does not model the effects of sediment deposition/resuspension to minimize computing time. The effects of sedimentation on cesium and plutonium transport in the Fourmile Branch were studied recently and the results from these studies indicated that the downstream cesium and plutonium peak concentrations were significantly reduced due to the effects of sedimentations. The STREAM II-V2 was upgraded to account for the effect of sedimentation on aqueous transport of cesium and plutonium released from H-Area.
Date: February 21, 2002
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department

Benchmarking of FLOWTRAN with Mark-22 mockup flow excursion test data from Babcock Wilcox

Description: Version 16.2 of the FLOWTRAN code with a Savannah River Site (SRS) working criterion (St=0.00455) for the onset of significant void (OSV) was benchmarked against power and flow excursion data derived from tests at the Babcock Wilcox Alliance Research Center test facility. The analyses show that FLOWTRAN accurately predicts the mockup test assembly thermal-hydraulic behavior during the steady state and LOCA transient conditions, and that FLOWTRAN with a Savannah River Site (SRS) working limits criterion (St=0.00455) conservatively predicts the OFI power. Results for LOCA simulations which include a power decay transient for a safety rod SCRAM are shown below. For all of these tests, the calculated test assembly initial power or operating power limit was at least 15% below the initial power level for which the test assembly went into flow instability. These calculations were made using the SRS LOCA FI limits methodology ada ted to the test assembly.
Date: November 1, 1991
Creator: Chen, K.F.
Partner: UNT Libraries Government Documents Department